Magneto-generator.



O. H. H. HEINS.

MAGNETO GENERATOR.

APPLICATION FILED MAR. 9, 190a.

3 SHEET s EET 2.

Patented M 0. H. H. HEINS.

MAGNETO GENERATOR. APPLICATION FILED MAR. 9. 1909.

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O. H. H. HEINS.

MAGNETO GENERATOR.

APPLICATION FILED MAR. 9. 1909.

1,140,1 55. Patented May 18, 1915.

3 SHEETSSHEET 3- OTTO H. H. HEINS, OF EDGEWATER-ON-HUDSON, NEW JERSEY.

MAGNETO-GENERATOR.

Specification of Letters Patent.

Patented May 18, 1915.

Application filed March 9, I909. Serial No. 482,358.

To all wlwm it may concern:

Be it known that I, O'r'ro H. H. HEINS, citizen of the German Empire,residing at Valley Place, Edgewater-on-Hudson, New Jersey, have inventedcertain new and useful Improvements in Magneto-Generators; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit a-ppertains, to make and use the same.

My invention relates to improvements in magneto-generators, that is tosay, electrical generators having permanent field magnets.

The employment of magneto-generators has been disadvantageous for manypurposes heretofore, owing to the impossibility of predetermining, witha sufficient approach to accuracy, the strength of the field magnets, itbeing extremely difficult, if not impossible, to magnetize a series ofpermanent magnets so that their pole-stren ths will be alike. Hence,even when new t ere is a wide variation in the output of differentmagnetos of the same type, due to the differences in strengths of theirrespective fields. Furthermore, owing to the gradual weakening of thepermanent magnets with age, and the variation in the amount of suchweakening, it is impossible to prepare tables of coefficients or factorsapplicable to all machines of the same type or even to any givenmachine. In short, the uncontrollable nature of the permanent magnets issuch as to make magnetos useless for work requiring great precision oran exact regulation of the condition of the field. These disadvantages,while merely causing great annoyance and inconveniences in certainfields for the employment of magnetos, for example, in ignition systems,become insuperable bars to the extended use of magnetos in other fields,for example, in connection with measuring instruments and the like.'

The object of my invention is to overcome these disadvantages and toprovide a magneto-generator which can be readily manufactured on acommercial scale and yet may have its field strength adjusted to anicety not only when first built, but at any time thereafter.

With this object in view my invention in its broadest sense comlprises agenerator having permanent field magnets and an adjustable magneticshunt or short-circuit for said field magnets.

For the purpose of adjusting the reluctance of the magnetic shunt orshort-circuit. either the cross-section of the iron or steel of theshunt, or the cross-section or length of its air gap, or the position ofthe shunt relative to the permanent magnets may be adjusted.

A further feature of my invention consists in making the magneticshort-circuit itself permanently magnetic and so arranging it that itsown flux may either reinforce or oppose the flux of the permanent fieldmagnets.

I will now describe some of the preferred specific embodiments of myinvention in connection with the accompanying drawings, in which Figure1 is a side elevation of a magnetogenerator embodying one form of myinvention, in which the adjustable short-circuiting device is of softiron; Fig. 2 a section on the line 2-2 of Fig. 1; Fig. 3 a plan viewpartly in section of a magnetogenerator embodying another form of myinvention in which the magnetic short-circuiting device is a permanentsteel magnet capable of being reversed, as more fully eX- plainedhereinafter; and Fig. 4 is a transverse section of the same.

Referring to the drawings, and more particularly to Figs. 1 and 2, A isthe base, B, B, the standards for the armature shaft journals, C thepermanent field magnets, D, D, the pole-pieces or shoes, and F thearmature of a magneto-generator. The base A and the standards B, B, areof non-magnetic material. E is a short-circuiting device, in the presentinstance comprising a plate of soft iron hinged at one end to one of thestandards, for example, the standard, B, the hinge connection beingindicated at 6. By means of this hinged connection the magneticshort-circuiting device may be swung down so as to lie upon and make aclose contact with the upper surfaces of the pole pieces D, D, or may beswung upward away from said pole-pieces to any desired extent. When inclose contact with the upper surfaces of the pole-pieces, the saidmagnetic short-circuiting device, forms such a good path for themagnetic flux of the permanent magnets that a large part, if notpractically all the flux which would otherwise pass through the armaturewill pass through the magnetic short-circuit. When the said magneticshort-circuiting device is raised very slightly from the pole-piecessome of the magnetic flux still will cross from one polepiece to theother through said magnetic short-circuiting device, the amountdepending upon the extent of the air-gap between the pole-pieces and thesaid magnetic shortcircuitin device, the remainder of the flux passingfiirough the armature. The higher the ma netic short-circuiting deviceis raised from t e pole-pieces, the less will be the amount of fluxpassing through the magnetic short-circuit and the greater the amount offiux passing through the armature. Hence by raising or lowering themagnetic short-circuit, the flux through the armature may be adjusted soas to give it the desired strength. Moreover, by reason of the variableangular relation of the shortcircuiting device to the pole pieces, thereluotances at different parts of the pole pieces may be made todifi'er.

Suitable means may be provided for adjusting the magneticshort-circuiting device to or from the pole-pieces, and for holding thesaid device in any position to which it is adjusted. In the presentexample, this adjusting means is as follows: The magneticshort-circuiting device is provided with a boss or enlargement 6 throughwhich is threaded an adjusting screw e whose lower end rests on the topof'the standard 13', the said screw having a head a preferably providedwith pin-holes into which a pin may be inserted for turning the screw,whereby the magnetic short-circuiting device is raised or lowered. Inorder to prevent the accidental rotation of the screw, a lock-nut e isprovided.

It is particularly to be noted that in the device just described, theshort-circuiting device is arranged on that side of the polepieces mostremote from theends of the field-magnets, thus insuring greaterefiiciency of the short-circuiting device than if it were at the ends ofthe field magnets, because in the latter position the magnetic circuitthrough the short-circuiting device is longer and therefore the magneticleakage from limb to limb of the permanent magnets is greater than whenthe magnetic shortcircuiting device is arranged as shown.

In Figs. 3 and 4; I have illustrated a modified form of the invention inwhich the reluctance of the magnetic shunt is adjusted by varying thecross-sectional area of the magnetic material in the shunt. In thisconstruction the pole-pieces D D are provided on their upper faces withgrooved ribs d (i which as shown in Fig. 3 do not extend the entirelength of said pole pieces; and between these ribs is mounted alongitudinally slidable plate E of magnetic material having tonguesslidin in the grooves of the ribs. Beneath this pIate E is a zinc plateG which forms'a protective cover for the armature F, and when the plateE is slid into the machine to its full extent, as shown in the drawings,it offers a good path for the passage of the magnetic flux from onepole-piece to the other, but when drawn out, to its greatest extent, asindicated in dotted lines in Fig. 3, it offers a much smallercross-section of magnetic material for the passage of the flux. Hence,by adjusting this plate in or out to the desired extent, thecross-sectional area of the magnetic material included in the magneticshunt may be varied as desired to accomplish the intended result. Forthe purpose of holding the said plate in any position to which it may beadjusted, any suitable means may be provided. In the present examplethis means may be as follows: The

plate E is provided with a slot as indicated at E", Fig. 3, and throughthis projects a thumb-screw e, which is threaded into a bridge-piece, H,Fig. 4, of non-magnetic material.

In the form of invention just described may be employed a permanentmagnet of steel, for example, whose poles are at the sides, as indicatedby the signs plus and minus Fig. 4. Then the effect of the shunt on thefield of the generator coils may be modified to a greater extent thanwith the ordinary iron plate, because in addition to the adjustment ofthe plate in or out, the said plate may be reversed, either by turningit end for end, or by turning it upside down, whereby the direction ofthe flux of the shunt plate may be the same as that of the permanentmagnets or opposite thereto, so that the said flux of the shunt platewill either reinforce the field due to the permanent magnets, or opposeand thereby weaken the same.

It will be clear from the foregoing that by my invention it becomespossible to manufacture commercially magneto-generators having fields ofpredetermined strengths, thus overcoming the disadvantages heretoforeexplained. .Also by 'my invention magnetos become practical for use inmeasuring systems, whereby all the advantages of the simplicity,durability and reliability of such 'machines become available for suchsystems. Such generators become particularly desirable in countingrevolutions of a working shaft, such as a ships propeller shaft,' thedriving shaft of an engine, etc. To perform such work, the generator maybe mounted directly on the shaft or may be geared thereto and isconnected to a galvanometer or ammeter which will be marked withreadings indicating the number of revolutions of a shaft in a given unitof time instead of the usual readings denoting strength of current.

Having thus fully described my invention, what I claim is 1. In amagneto-generator, the combination, with a permanent field-magnet, andan armature, of a reversible polarized magnetic short-circuiting devicearranged to short-circuit the flux through said armature.

2. In a magneto-generator, the combination, with a permanentfield-magnet having pole-pieces, and an armature between saidpole-pieces, of a reversible polarized magnetic short-circuiting devicearranged to be adjusted to vary the reluctance of the magneticshort-circuit.

3. In a magneto-generator, the combination, with a permanentfield-magnet, and a continuously rotatable armature coil in the field ofsaid permanent magnet, of a plate longitudinally adjustable between thelimbs of said field-magnet, and means for holding said plate in anydesired position.

In a magneto-generator, the combination, with a permanent field-magnet,and an armature coil in the field of said permanent magnet, of apolarized plate longitudinally adjustable between the limbs of saidfieldmagnet, and means for holding said plate in any desired position.

5. In a magneto-generator, the combination, with a permanent fieldmagnet having poles, and a continuously rotatable armature coil in thefield of said permanent magnet, of a magnetic short-circuiting devicearranged transversely to the direction of the flux and parallel to theaxis of the armature, said magnetic short-circuiting device beingadjustable in the direction of the axis of the armature to vary thereluctance of the magnetic shunt circuit to standardize the circuitthrough the armature, and means for securing said short circuitingdevice in adjusted position.

6. In a magneto-generator, the combination, with a plurality ofpermanent fieldmagnets, a pair of pole-pieces, common to all the saidfield magnets, and an armature rotatably mounted between saidpole-pieces, of a magnetic shunt device for shunting the field flux fromthe armature, means for adjusting said magnetic shunt device so as togive different reluctances at dilferent parts of the gap between thepole-pieces to standardize the flux through the armature and means forsecuring the shunt device in adjusted position. i

7. In a magneto-generator, the combination, with a plurality ofpermanent fieldmagnets, a pair of pole-pieces common to all of saidfield-magnets, and an armature rotatably mounted between saidpole-pieces, of a magnetic shunt device, arranged between the pair ofpole-pieces and the yoke of the magnet, and means for adjusting andholding said magnetic shunt device in different relations to thepole-pieces whereby the flux through said pole-pieces may be differentlyshort-circuited at different points, and the flux through the armaturestandardized.

8. In a magneto-generator, the combination, with a plurality ofpermanent field magnets, and an armature coil in the field of all ofsaid magnets, of means for shunting the flux of said magnets from thearmature coil, to unequal extents for the respective field magnets tostandardize the flux through the armature.

9. In a magneto generator, the combination, with a plurality ofpermanent field magnets assembled in axial alinement and a rotatablearmature in the field of said magnets, of amagnetic shunt device movablesubstantially axially of the assembled.mag nets to vary the flux betweenthe poles of said magnets.

In witness whereof I hereunto affix my signature in the presence of twowitnesses.

OTTO H. H. HEINS.

Witnesses:

ROGER B. WHITMAN, A. H. BARTSCH.

